CA1098390A - Four-stroke reciprocatory internal combustion engine and method of operating such an engine - Google Patents
Four-stroke reciprocatory internal combustion engine and method of operating such an engineInfo
- Publication number
- CA1098390A CA1098390A CA290,288A CA290288A CA1098390A CA 1098390 A CA1098390 A CA 1098390A CA 290288 A CA290288 A CA 290288A CA 1098390 A CA1098390 A CA 1098390A
- Authority
- CA
- Canada
- Prior art keywords
- air
- engine
- cylinder
- phase
- during
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000002485 combustion reaction Methods 0.000 title claims abstract description 89
- 238000000034 method Methods 0.000 title claims description 23
- 239000000446 fuel Substances 0.000 claims abstract description 78
- 230000002000 scavenging effect Effects 0.000 claims abstract description 47
- 239000000203 mixture Substances 0.000 claims abstract description 46
- 230000006698 induction Effects 0.000 claims abstract description 28
- 239000007789 gas Substances 0.000 claims description 35
- 230000001276 controlling effect Effects 0.000 claims description 12
- 230000006835 compression Effects 0.000 claims description 10
- 238000007906 compression Methods 0.000 claims description 10
- 239000012530 fluid Substances 0.000 claims description 8
- 238000004891 communication Methods 0.000 claims description 7
- 230000003111 delayed effect Effects 0.000 claims description 7
- 238000011144 upstream manufacturing Methods 0.000 claims description 2
- 239000000567 combustion gas Substances 0.000 claims 3
- 230000001939 inductive effect Effects 0.000 claims 3
- 230000001419 dependent effect Effects 0.000 claims 1
- 238000002347 injection Methods 0.000 claims 1
- 239000007924 injection Substances 0.000 claims 1
- 230000000694 effects Effects 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 17
- 238000007254 oxidation reaction Methods 0.000 description 3
- 238000013459 approach Methods 0.000 description 2
- 230000000875 corresponding effect Effects 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000002459 sustained effect Effects 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B31/00—Modifying induction systems for imparting a rotation to the charge in the cylinder
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/30—Controlling fuel injection
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B31/00—Modifying induction systems for imparting a rotation to the charge in the cylinder
- F02B2031/006—Modifying induction systems for imparting a rotation to the charge in the cylinder having multiple air intake valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B75/00—Other engines
- F02B75/02—Engines characterised by their cycles, e.g. six-stroke
- F02B2075/022—Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle
- F02B2075/027—Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle four
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/0002—Controlling intake air
- F02D2041/0015—Controlling intake air for engines with means for controlling swirl or tumble flow, e.g. by using swirl valves
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
Abstract
ABSTRACT OF THE DISCLOSURE
A four-stroke reciprocatory internal combustion engine has a scavenging phase in which air is admitted under pressure into the cylinder and has a swirl gene-rating phase in which a high-speed jet of air is admitted under pressure into the cylinder so as to swirl air fuel mixture charge in the cylinder around the cylinder axis.
The engine has, in addition to an intake valve that controls induction of air fuel mixture into the cylinder, a separate air inlet valve which effects the scavenging phase and swirl generating phase.
A four-stroke reciprocatory internal combustion engine has a scavenging phase in which air is admitted under pressure into the cylinder and has a swirl gene-rating phase in which a high-speed jet of air is admitted under pressure into the cylinder so as to swirl air fuel mixture charge in the cylinder around the cylinder axis.
The engine has, in addition to an intake valve that controls induction of air fuel mixture into the cylinder, a separate air inlet valve which effects the scavenging phase and swirl generating phase.
Description
1~8390 BACKGROUND OF THE INVENTION
This invention relates to a four-stroke recirpo-catory internal combustion engine and to a method of operating such a four-stroke reciprocatory internal combustion engine.
The permissible limits of exhaust emissions in certain countries such as Japan are shown in the following tabulation:
HC CO NOx g/mile g/mile g/mile 1978 standard (Japan) 0.40 3.36 0.40 Car manufactures are now striving hard to develop a fuel economy engine which meets the above stringent standard.
In present spark ignition internal combustion engines under idle and deceleration conditions air fuel ratio (A/F) of the charge in the cylinder must be kept rich enough to allow the engine to run smoothly because under these conditions the rate of residual gas of the charge in the cylinder increases abruptly. Emprically it is known that the engine stability is directly affected by G/F, rather than A/F, of the charge in the cylinder, where, G= (intake air content) + (residual gas content), and that there is optimum range of G/F around which .the engine runs smoothly. In practice, A/F of the charge 10~ 0 in the cylinder is kept ex~essively rich and the rate Of residual gas of the charge is considerably great under idle and deceleration conditions so that the exhaust gas resulting from the combustion of the charge will certain high HC and CO under there conditions.
To reduce CO and HC, it is therefore necessary to supply secondary air under idle and deceleration conditions for facilitating oxidation reaction of CO and HC in an exhaust gas treatment device.
If, under idle and deceleration conditions, the engine can run smoothly when A/F of the charge in the cyliner is around the stoichiometry, CO and HC levels will be lowered. This, however, is not yet accomplished and its accomplishment is strongly desired for the purpose of providing a fuel economy low emission engine.
It is also desired to operate the engine, under part load conditions, on the charge whose A/F is around the stoichometry.
To attain fuel economy of a car, it is effective to reduce the volume of the cylinder. So, it is desired to increase the power output of the engine under full load conditions.
Prior Art It has been proposed, for the purpose of preventing knocking, to admit air, under pressure, into the cylinder ~0~
during the end portion of the compression stroke to keep the charge in the cylinder cool and again during the end portion of the exhaust stroke to cool the exhaust valve and spark plug. The problem resides in that high charging pressure, i.e., pressure above 10 kg/cm , is necessary for the admission of air into the cylinder during the end portion of the compression stroke.
It has also been proposed, for the purpose of expelling the residual gas from the cylinder, to admit air, under pressure, into the cylinder during the exhaust stroke.
It has also been proposed, for facilitating oxidation of HC and ~O contents of the exhaust gas, to admit air, under pressure, into the cylinder during the end portion of the expansion stroke and the exhaust stroke.
It has been proposed that an air fuel mixture is inducted into the cylinder through an intake valve to swixl around the cylinder axis in one direction and an air is admitted under atmospheric pressure through an air inlet valve during the beginning portion of the in-take stroke to swirl around the cylinder axis in the opposite direction to produce a stratified charge com-prising an ignitable cloud in the proximity of a spark plug.
It has been proposed that an air fuel mixture is _ ~ _ 10~8390 . , inducted into the cylinder through an intake valve during the intake stroke and an air is admitted under atmospheric pressure through an air inlet valve to swirl around the cylinder axis to produce a stratified charge comprisinq an lgnitable cloud in the proximity of a spark plug and to accomplish fast combustion of the charge in the cylinder.
It has been proposed that an air fuel mixture is inducted into the cylinder through an intake valve to swirl around the cylinder axis and an air, in a jet form, is admitted under atmospheric pressure through an air inlet valve all through the intake stroke to swirl within a plane substantially parallel to the cylinder axis to accomplish fast combustion. The jet of air is directed toward the electrode o the spark plug to scavenge the same.
SUMMARY OF THE INVENTION
-It is an object of this invention to improve fuel economy of a reciprocatory internal combustion engine.
It is another object of this invention to improve fuel economy of a reciprocatory internal combustion engine and to reduce emission levels of the engine ~elow the stringent 1978 standard in Japan.
According to this invention, the admission of air, under pressure, into cylinder of a reciprocatory internal 10~8390 - combustion is effected to scavenge the cylinder during the exhaust stroke, the induction of air fuel mixture is effected during the intake stroke, and the admission of air, under pressure, into the cylinder to cause the charge in the cylinder to swirl generally around the cylinder axis. Because the residual gas fraction of the charge in the cylinder is replaced with the same amount of pure air, the combustion efficiency has been improved under part load, idle and deceleration conditions and fuel consumption and emission levels have been :.
reduced. Under full load conditions, the rate of fuel of the charge in the cylinder can be increased because there exists substantially no residual gas as a result of the replacement of the residual gas fraction of the charge by the same amount of pure air, increasing the power output and torque of the engine under these con-ditions.
It is another object of this invention to scavenge cylinder of a reciprocatory internal combustion engine under all operating conditions of the engine.
It is another object of this invention to provide a reciprocatory internal combustion engine having an intake valve for the induction of air fuel mixture and an air inlet valve for the admission under pressure of air. Because, swirl of the charge in the cylinder is _ ,~ _ 10~8390 produced by a high-speed jet of air from the air inlet valve, an intake arrangement to impart a force to the air fuel mixture as it flows the intake valve, which would increase resistance to the inflowinq mixture, is unnecessary in the engine of the invention .
It is another object of this invention to precisely control the amount of air per each admission of air into cylinder of a reciprocatory internal combustion engine in response to engine operating conditions to meet the amount of residual gas which varies against the variation of loads and engine speed.
It is another object of the invention to reduce the cubic capacity of a reciprocatory internal combustion en~ine with the same power output.
It is another object of the invention to provide a reciprocatory internal combustion engine for automobiles which is fuel-stingy and capable of producing high power.
It is another ob~ect of the invention to provide a reciprocatory internal combustion engine which runs smoothly on the charge whose A/F not less than stoichometry under idle and deceleration conditions.
In accordance with the above objects, the invention herein claimed essentially lies in the provision of a method of operating a four-stroke reciprocatory internal combustion engine having a cylinder with a piston reciprocating therein.
This method essentially comprises a first step of admitting air under pressure into the cylinder during a scavenging phase which overlaps the final portion of the exhaust stroke of the piston so as to scavenge the cylinder; a second step of inducting air fuel mixture into the cylinder during the intake stroke of the piston; and a third step of admitting air under pressure into the cylinder during a swirl generating phase " ~, 10~8390 which overlaps a portion of the intake stroke of the piston which follows the exhaust stroke so that air under pressure mixes with the air fuel mixture and causes the resultant charge to swirl around the cylinder axis.
The invention also lies in the provision of an internal combustion engine which essentially comprises: means defining a cylinder having a combustion chamber; an intake means for inducting air fuel mixture chamber into said combustion chamber during an induction phase of the engine, the intake means including a first inlet valve for controlling fluid communication between the intake means and said combustion chamber; an exhaust means for exhausting the exhaust gas resulting from the com-bustion of the air fuel mixture from the combustion chamber during an exhaust phase of the engine, the exhaust means including an exhaust valve for controlling fluid communication between the combustion chamber and the exhaust means; an additional intake means for admitting air under pressure into the cylinder and which is so constructed and arranged as to direct the air under prffs-sure into the cylinder in a direction substantially tangential with respect to the wall of the cylinder so that the air under pressure swirls around the cylinder in one rotational direction, the additional intake means including a pump driven by the engine which supplies the air under pressure, a second inlet valve or controlling the fluid communication between *he pump and the com-bustion chamber and means operatively connected to the second inlet valve for opening it during a scavenging phase of the exhaust phase so as to scavenge the hot residual gases from the cylinder and during a swirl generating phase of the induction phase so that the air under pressure mixes with the air fuel mixture fed into the combustion chamber from the intake means and induces the resultant air fuel mixture to swirl in the one rotational direction.
1~8390 An embodiment of the invention will now be described with reference to the appended drawings wherein:
Fig. 1 is diagrammatic view of a four-stroke s - 7a -.~, .
10"8390 reciprocatory internal combustion engine of the invention;
Fig. 2A is a top plan view of a valve arrangement of the internal co~bustion engine shown in Fig. l;
Figs. 2B and 2C are similar views to Fig. 2A showing different examples;
Fig. 3 is a valve timing diagram of the intake, exhaust and air inlet valves of the engine shown in Fig. l;
Fig. 4A is a valve lift diagram of the air inlet valve;
Fig. 4B is a similar view to Fig. 4A showing another example;
Fig. 5 is a graph showing a torque versus engine speed curve of the engine of the invention under full load conditions and that of the conventional engine;
Fig. 5 is a graph showing a fuel consumption versus air fuel ratio curve of the engine of the invention under idle condition and that of the conventional engine;
Fig. 7 is a valve timing diagram of the intake, exhaust and air inlet valves of the engine shown in Fig. l;
Fig. 8 is a diagrammatic view of the flow control device shown in Fig~ l;
Figs. 9A and 9B are timing diagrams of signals from the control circuit shown in Fig. 8;
10~83~0 Fig. 10 is a graph showing the required admission of air through the additional intake port as a function of the engine speed and induction vacuum;
Fig. 11 is another example of a valve timing diagram of the air inlet valve of the engine shown in Fig. l;
and Fig. 12 is a cam for the air inlet valve and designed to follow the valve timing diagram shown in Fig. 11.
DETAILED DESCRIPTION OF THE PREFERRED E~BODIMENTS
__ _ Referring to Figs. 1 and 2A of the accompanying drawings, a four-stroke internal combustion engine comprises a cylinder 1, a piston 2 reciprocating in the cylinder and a cylinder head 3 secured to the cylinder.
The cylinder 1, piston 2 and cylinder head 3 cooperate to form a combustion chamber 4.
The cylinder head 3 has an intake port bore 5, an exhaust port bore 6, an additional intake port bore 7 all opening to the combustion chamber 1. An intake valve 8 cooperating with the intake port bore 5, an exhaust valve 9 and an air inlet valve 10 cooperating with the additional intake port bore 7 are supported in the cylinder head. As shown in Fig. 2A, in order to impart a force to inflowing air to swirl generally around 2S the cylinder axis, the air inlet valve 10 has a valve 10~
shroud 11. The head of the intake valve 8 is disposed downstream of the head of the intake valve 8 is disposed downstream of the head of the air inlet valve 10 with respect to the swirling air (see arrows shown in Fig. 2A), S the head of the exhaust valve 9 is disposed downstream of the head of the intake valve 8 with respect to the swirling air, and the electrode of a spark plug 12 is exposed to the combustion chamber 1 at a location positioned downstream of the head of the intake valve 8 and upstream of the head of the exhaust valve 9 with respect to the swirling air.
During a scavenging phase which overlaps the exhaust stroke the air inlet valve 10 opens to admit air under pressure into the cylinder 1 through the additional intake port bore 7 to scavenge the cylinder 1 by expelling the exhaust gas from the cylinder 1 through the exhaust port bore 6 because the exhaust valve 9 remains open.
Because the scavenging air swirls around the cylinder axis in a manner to expel the exhaust gas toward the exhaust port bore 6 in the valve arrangement shown in Fig. 2A, the scavenging efficiency is quite high with this valve arrangement.
During the intake stroke the intake valve 8 opens and the piston 2 draws an air fuel mixture into the cylinder 1 through the intake port bore S.
~0~8390 During a swirl generating phase which overlaps the intake stroke the air inlet valve lO opens to admit a high-speed jet of air into the cylinder 1 under pressure through the additional intake port bore 7 so as to swirl S the air fuel mixture generally around the cylinder axis.
Fig. 3 shows by way of example a timing diagram for the exhaust valve 9, intake valve 8 and air inlet valve lO. The opening period of the exhaust valve 9 and the opening period of the intake valve 8 are denoted by X and Y, respectively, while the opening period of the air inlet valve 10 is denoted by Z. The air inlet valve 10 opens to initiate the scavenging phase and closes to terminate the succeeding swirl generating phase. In this example the swirl generating phase over-laps and succeeds the scavenging phase.
Because, in a conventional reciprocatory internalcombustion engine, the rate of residual gas of the charge in a cylinder varys against the variations of the engine operating conditions, it is preferable to control the amount, by weight, of air to be admitted into the cylinder 1 through the additional intake port 7 upon each opening period of the air inlet valve 9 in response to operating conditions of the engine.
To this end a flow control device 13 is provided to control fluid flow through a conduit 14 connecting lQ~8390 the outlet of a surge tank 15 to the additional intake port bore 7, see Fig. 1. An air pump 16 draws in the atmospherie air through an air cleaner 17 and transfers it toward the additional intake port bore 7 through a eheek valve 18, surge tank 15 and conduit 14 under pressure above atmospheric pressure (about 1.2-2.0 kg/cm ).
The air pump 16 is connected to the engine crankshaft of the engine through a meehanieal drive to be aetuated thereby. Alternatively, an air compressor may be used instead of the air pump. The air compressor is connected - to a turbine disposed in the engine exhaust system with a shaft similar to that used on the present turbo-charged engine.
Going into to the detail of the flow eontrol deviee 13 taking reference to Figs. 8 to 10, a flow control valve 20 is fluidly disposed in the conduit 14 (see Fig. 8). A vacuum servo 21 is mounted to the conduit 14 and has a diaphragm 21a to whieh the valve stem of the valve 20 is fixedly connected, an atmospherie chamber 21b below (viewing Fig. 8) the diaphragm 21a, a vacuum ehamber 21c above (viewing Fig. 8) the diaphragm 21a, and a spring 21d mounted within the vacuum chamber 21c to aet against the diaphragm 21a to bias the valve 20 to the illustrated close position in which the conduit
This invention relates to a four-stroke recirpo-catory internal combustion engine and to a method of operating such a four-stroke reciprocatory internal combustion engine.
The permissible limits of exhaust emissions in certain countries such as Japan are shown in the following tabulation:
HC CO NOx g/mile g/mile g/mile 1978 standard (Japan) 0.40 3.36 0.40 Car manufactures are now striving hard to develop a fuel economy engine which meets the above stringent standard.
In present spark ignition internal combustion engines under idle and deceleration conditions air fuel ratio (A/F) of the charge in the cylinder must be kept rich enough to allow the engine to run smoothly because under these conditions the rate of residual gas of the charge in the cylinder increases abruptly. Emprically it is known that the engine stability is directly affected by G/F, rather than A/F, of the charge in the cylinder, where, G= (intake air content) + (residual gas content), and that there is optimum range of G/F around which .the engine runs smoothly. In practice, A/F of the charge 10~ 0 in the cylinder is kept ex~essively rich and the rate Of residual gas of the charge is considerably great under idle and deceleration conditions so that the exhaust gas resulting from the combustion of the charge will certain high HC and CO under there conditions.
To reduce CO and HC, it is therefore necessary to supply secondary air under idle and deceleration conditions for facilitating oxidation reaction of CO and HC in an exhaust gas treatment device.
If, under idle and deceleration conditions, the engine can run smoothly when A/F of the charge in the cyliner is around the stoichiometry, CO and HC levels will be lowered. This, however, is not yet accomplished and its accomplishment is strongly desired for the purpose of providing a fuel economy low emission engine.
It is also desired to operate the engine, under part load conditions, on the charge whose A/F is around the stoichometry.
To attain fuel economy of a car, it is effective to reduce the volume of the cylinder. So, it is desired to increase the power output of the engine under full load conditions.
Prior Art It has been proposed, for the purpose of preventing knocking, to admit air, under pressure, into the cylinder ~0~
during the end portion of the compression stroke to keep the charge in the cylinder cool and again during the end portion of the exhaust stroke to cool the exhaust valve and spark plug. The problem resides in that high charging pressure, i.e., pressure above 10 kg/cm , is necessary for the admission of air into the cylinder during the end portion of the compression stroke.
It has also been proposed, for the purpose of expelling the residual gas from the cylinder, to admit air, under pressure, into the cylinder during the exhaust stroke.
It has also been proposed, for facilitating oxidation of HC and ~O contents of the exhaust gas, to admit air, under pressure, into the cylinder during the end portion of the expansion stroke and the exhaust stroke.
It has been proposed that an air fuel mixture is inducted into the cylinder through an intake valve to swixl around the cylinder axis in one direction and an air is admitted under atmospheric pressure through an air inlet valve during the beginning portion of the in-take stroke to swirl around the cylinder axis in the opposite direction to produce a stratified charge com-prising an ignitable cloud in the proximity of a spark plug.
It has been proposed that an air fuel mixture is _ ~ _ 10~8390 . , inducted into the cylinder through an intake valve during the intake stroke and an air is admitted under atmospheric pressure through an air inlet valve to swirl around the cylinder axis to produce a stratified charge comprisinq an lgnitable cloud in the proximity of a spark plug and to accomplish fast combustion of the charge in the cylinder.
It has been proposed that an air fuel mixture is inducted into the cylinder through an intake valve to swirl around the cylinder axis and an air, in a jet form, is admitted under atmospheric pressure through an air inlet valve all through the intake stroke to swirl within a plane substantially parallel to the cylinder axis to accomplish fast combustion. The jet of air is directed toward the electrode o the spark plug to scavenge the same.
SUMMARY OF THE INVENTION
-It is an object of this invention to improve fuel economy of a reciprocatory internal combustion engine.
It is another object of this invention to improve fuel economy of a reciprocatory internal combustion engine and to reduce emission levels of the engine ~elow the stringent 1978 standard in Japan.
According to this invention, the admission of air, under pressure, into cylinder of a reciprocatory internal 10~8390 - combustion is effected to scavenge the cylinder during the exhaust stroke, the induction of air fuel mixture is effected during the intake stroke, and the admission of air, under pressure, into the cylinder to cause the charge in the cylinder to swirl generally around the cylinder axis. Because the residual gas fraction of the charge in the cylinder is replaced with the same amount of pure air, the combustion efficiency has been improved under part load, idle and deceleration conditions and fuel consumption and emission levels have been :.
reduced. Under full load conditions, the rate of fuel of the charge in the cylinder can be increased because there exists substantially no residual gas as a result of the replacement of the residual gas fraction of the charge by the same amount of pure air, increasing the power output and torque of the engine under these con-ditions.
It is another object of this invention to scavenge cylinder of a reciprocatory internal combustion engine under all operating conditions of the engine.
It is another object of this invention to provide a reciprocatory internal combustion engine having an intake valve for the induction of air fuel mixture and an air inlet valve for the admission under pressure of air. Because, swirl of the charge in the cylinder is _ ,~ _ 10~8390 produced by a high-speed jet of air from the air inlet valve, an intake arrangement to impart a force to the air fuel mixture as it flows the intake valve, which would increase resistance to the inflowinq mixture, is unnecessary in the engine of the invention .
It is another object of this invention to precisely control the amount of air per each admission of air into cylinder of a reciprocatory internal combustion engine in response to engine operating conditions to meet the amount of residual gas which varies against the variation of loads and engine speed.
It is another object of the invention to reduce the cubic capacity of a reciprocatory internal combustion en~ine with the same power output.
It is another object of the invention to provide a reciprocatory internal combustion engine for automobiles which is fuel-stingy and capable of producing high power.
It is another ob~ect of the invention to provide a reciprocatory internal combustion engine which runs smoothly on the charge whose A/F not less than stoichometry under idle and deceleration conditions.
In accordance with the above objects, the invention herein claimed essentially lies in the provision of a method of operating a four-stroke reciprocatory internal combustion engine having a cylinder with a piston reciprocating therein.
This method essentially comprises a first step of admitting air under pressure into the cylinder during a scavenging phase which overlaps the final portion of the exhaust stroke of the piston so as to scavenge the cylinder; a second step of inducting air fuel mixture into the cylinder during the intake stroke of the piston; and a third step of admitting air under pressure into the cylinder during a swirl generating phase " ~, 10~8390 which overlaps a portion of the intake stroke of the piston which follows the exhaust stroke so that air under pressure mixes with the air fuel mixture and causes the resultant charge to swirl around the cylinder axis.
The invention also lies in the provision of an internal combustion engine which essentially comprises: means defining a cylinder having a combustion chamber; an intake means for inducting air fuel mixture chamber into said combustion chamber during an induction phase of the engine, the intake means including a first inlet valve for controlling fluid communication between the intake means and said combustion chamber; an exhaust means for exhausting the exhaust gas resulting from the com-bustion of the air fuel mixture from the combustion chamber during an exhaust phase of the engine, the exhaust means including an exhaust valve for controlling fluid communication between the combustion chamber and the exhaust means; an additional intake means for admitting air under pressure into the cylinder and which is so constructed and arranged as to direct the air under prffs-sure into the cylinder in a direction substantially tangential with respect to the wall of the cylinder so that the air under pressure swirls around the cylinder in one rotational direction, the additional intake means including a pump driven by the engine which supplies the air under pressure, a second inlet valve or controlling the fluid communication between *he pump and the com-bustion chamber and means operatively connected to the second inlet valve for opening it during a scavenging phase of the exhaust phase so as to scavenge the hot residual gases from the cylinder and during a swirl generating phase of the induction phase so that the air under pressure mixes with the air fuel mixture fed into the combustion chamber from the intake means and induces the resultant air fuel mixture to swirl in the one rotational direction.
1~8390 An embodiment of the invention will now be described with reference to the appended drawings wherein:
Fig. 1 is diagrammatic view of a four-stroke s - 7a -.~, .
10"8390 reciprocatory internal combustion engine of the invention;
Fig. 2A is a top plan view of a valve arrangement of the internal co~bustion engine shown in Fig. l;
Figs. 2B and 2C are similar views to Fig. 2A showing different examples;
Fig. 3 is a valve timing diagram of the intake, exhaust and air inlet valves of the engine shown in Fig. l;
Fig. 4A is a valve lift diagram of the air inlet valve;
Fig. 4B is a similar view to Fig. 4A showing another example;
Fig. 5 is a graph showing a torque versus engine speed curve of the engine of the invention under full load conditions and that of the conventional engine;
Fig. 5 is a graph showing a fuel consumption versus air fuel ratio curve of the engine of the invention under idle condition and that of the conventional engine;
Fig. 7 is a valve timing diagram of the intake, exhaust and air inlet valves of the engine shown in Fig. l;
Fig. 8 is a diagrammatic view of the flow control device shown in Fig~ l;
Figs. 9A and 9B are timing diagrams of signals from the control circuit shown in Fig. 8;
10~83~0 Fig. 10 is a graph showing the required admission of air through the additional intake port as a function of the engine speed and induction vacuum;
Fig. 11 is another example of a valve timing diagram of the air inlet valve of the engine shown in Fig. l;
and Fig. 12 is a cam for the air inlet valve and designed to follow the valve timing diagram shown in Fig. 11.
DETAILED DESCRIPTION OF THE PREFERRED E~BODIMENTS
__ _ Referring to Figs. 1 and 2A of the accompanying drawings, a four-stroke internal combustion engine comprises a cylinder 1, a piston 2 reciprocating in the cylinder and a cylinder head 3 secured to the cylinder.
The cylinder 1, piston 2 and cylinder head 3 cooperate to form a combustion chamber 4.
The cylinder head 3 has an intake port bore 5, an exhaust port bore 6, an additional intake port bore 7 all opening to the combustion chamber 1. An intake valve 8 cooperating with the intake port bore 5, an exhaust valve 9 and an air inlet valve 10 cooperating with the additional intake port bore 7 are supported in the cylinder head. As shown in Fig. 2A, in order to impart a force to inflowing air to swirl generally around 2S the cylinder axis, the air inlet valve 10 has a valve 10~
shroud 11. The head of the intake valve 8 is disposed downstream of the head of the intake valve 8 is disposed downstream of the head of the air inlet valve 10 with respect to the swirling air (see arrows shown in Fig. 2A), S the head of the exhaust valve 9 is disposed downstream of the head of the intake valve 8 with respect to the swirling air, and the electrode of a spark plug 12 is exposed to the combustion chamber 1 at a location positioned downstream of the head of the intake valve 8 and upstream of the head of the exhaust valve 9 with respect to the swirling air.
During a scavenging phase which overlaps the exhaust stroke the air inlet valve 10 opens to admit air under pressure into the cylinder 1 through the additional intake port bore 7 to scavenge the cylinder 1 by expelling the exhaust gas from the cylinder 1 through the exhaust port bore 6 because the exhaust valve 9 remains open.
Because the scavenging air swirls around the cylinder axis in a manner to expel the exhaust gas toward the exhaust port bore 6 in the valve arrangement shown in Fig. 2A, the scavenging efficiency is quite high with this valve arrangement.
During the intake stroke the intake valve 8 opens and the piston 2 draws an air fuel mixture into the cylinder 1 through the intake port bore S.
~0~8390 During a swirl generating phase which overlaps the intake stroke the air inlet valve lO opens to admit a high-speed jet of air into the cylinder 1 under pressure through the additional intake port bore 7 so as to swirl S the air fuel mixture generally around the cylinder axis.
Fig. 3 shows by way of example a timing diagram for the exhaust valve 9, intake valve 8 and air inlet valve lO. The opening period of the exhaust valve 9 and the opening period of the intake valve 8 are denoted by X and Y, respectively, while the opening period of the air inlet valve 10 is denoted by Z. The air inlet valve 10 opens to initiate the scavenging phase and closes to terminate the succeeding swirl generating phase. In this example the swirl generating phase over-laps and succeeds the scavenging phase.
Because, in a conventional reciprocatory internalcombustion engine, the rate of residual gas of the charge in a cylinder varys against the variations of the engine operating conditions, it is preferable to control the amount, by weight, of air to be admitted into the cylinder 1 through the additional intake port 7 upon each opening period of the air inlet valve 9 in response to operating conditions of the engine.
To this end a flow control device 13 is provided to control fluid flow through a conduit 14 connecting lQ~8390 the outlet of a surge tank 15 to the additional intake port bore 7, see Fig. 1. An air pump 16 draws in the atmospherie air through an air cleaner 17 and transfers it toward the additional intake port bore 7 through a eheek valve 18, surge tank 15 and conduit 14 under pressure above atmospheric pressure (about 1.2-2.0 kg/cm ).
The air pump 16 is connected to the engine crankshaft of the engine through a meehanieal drive to be aetuated thereby. Alternatively, an air compressor may be used instead of the air pump. The air compressor is connected - to a turbine disposed in the engine exhaust system with a shaft similar to that used on the present turbo-charged engine.
Going into to the detail of the flow eontrol deviee 13 taking reference to Figs. 8 to 10, a flow control valve 20 is fluidly disposed in the conduit 14 (see Fig. 8). A vacuum servo 21 is mounted to the conduit 14 and has a diaphragm 21a to whieh the valve stem of the valve 20 is fixedly connected, an atmospherie chamber 21b below (viewing Fig. 8) the diaphragm 21a, a vacuum ehamber 21c above (viewing Fig. 8) the diaphragm 21a, and a spring 21d mounted within the vacuum chamber 21c to aet against the diaphragm 21a to bias the valve 20 to the illustrated close position in which the conduit
2~ 14 is closed by the valve 20. A vacuum conduit 21e lQ~8390 connects the outlet of a source of constant vacuum, in the form of a vacuum accumulator 22, to the vacuum chamber 21c. The vacuum accumulator 22 is connected to the source of the engine induction vacuum through a check valve 23. A pressure regulator 24 is mounted to thé vacuum accumulator 22 to keep the pressure within the accumulator 22 constant irrespective of the engine operating conditions. The vacuum conduit 21e is provided with an orifice 25 therein and an air bleed conduit 26 has one end connected to the vacuum conduit 21e at a location intermediate.the orifice 25 and the vacuum chamber 21c. An air bleed orifice 26 is provided within the air bleed conduit 26 at an opposite end thereof.
A solenoid valve 28 is arranged to control flow through the air bleed conduit 26. When not energized, the solenoid valve 28 closes the air bleed conduit 26, while, when energized, it opens the air bleed conduit 26. A
control circuit 30, only diagram~atically shown in Fig. 8, is electrically circuited with the solenoid valve 28.
The control circuit 30 shown in Fig. 8 comprises a clock counter 31 which generates a reset signal 32 at regular intervals. The reset signal 32 is fed to an integrator 33 and also to a flip flop 34 to reset them. An electrical signal 35 representing the engine 10~8390 speed (the engine r.p.m.) is fed to the integrator 33.
An output signal voltage 36 from the integrator 33 rises at a faster rate when the engine speed is high than when the engine speed is low. This output signal voltage 36 is fed to a comparator 37 to which a reference signal voltage 38 representing the engine induction vacuum is fed. The reference signal voltage 38 is higher when the engine induction vacuum is high, i.e., when engine load is low, than when the induction vacuum is low, i.e., when engine load is high. The comparator 37 feeds - a reset signal 39 to the flip flop 34 when the signal 36 exceeds the signal 38. Since time period after the instance of the reset signal 32 to the instance of the reset signal 39 is variable in response to the engine speed and induction vacuum, the flip flop 34 will produce a pulse signal 40 having a pulse width variable in response to the engine speed and induction vacuum. This pulse signal 40 is amplified by means of an amplifier 41 and then used to energize the solenoid valve 28 so that the solenoid will be energized for a time corres-ponding to the pulse width.
Fig. 9A shows a timing diagram representing the condition that the engine speed is high and induction vacuum is low, while Fig. 9B a timing diagram representing the condition that the engine speed is low and induction ~Qg8390 \
vacuum is high. Fig. lO shows a graph plotting the required amount of scavenging air for expelling the residual gas from a cylinder as against the engine speed and induction vacuum. It will now be understood that with the valve 20 the amount of air to be admitted into the cylinder 1 through the additional intake port bore 7 under the control of the air inlet valve 10 (see Fig. 1) will be varied along the graph shown in Fig. 10.
It is found that the best scavenging efficiency has been obtained when more than 50%, by weight, of the total amount, by weight, of air admitted during each opening period of the air inlet valve 10 is admitted into the cylinder l during the scavenging phase before the top dead center position of the piston 2. This can be effected by selecting a cam profile or a valve timing for the air inlet valve 10.
As will be noted from the timing diagram shown in Fig. 3, because the exhaust valve 9 is closing when the air inlet valve 10 begins to open and is almost closed at the top dead center position, the scavenging effici-ency is decreased abruptly as the piston 2 approaches the top dead center.
When the intake valve 8 begins to open, the exhaust gas tends to be drawn into the intake port bore 5 due to vacuum in the intake manifold, and the scavenging - lS -lQ 83~0 efficiency is quite low under this condition.
Thus it will be understood that for the purpose of increasing the scavenging efficiency the cam profile for the air inlet valve 9 should be desinged so that right after the opening of the air inlet valve 9 a great amount of air is admitted into the cylinder 1 to thereby expel as much residual gas from the cylinder as possible before the opening of the intake valve 8.
The opening degree of the air inlet valve 9 should be reduced when the intake valve 8 is opening to increase the inflow velocity of air thereby generating a strong swirl which is effective in increasing the combustion speed.
Therefore, as shown in Fig. 4A the valve lift diagram for the air inlet valve 9 should preferably be set so that a great amount of air is admitted into the cylinder 1 at the initial stage of the valve opening period and more than 50% air, of the total amount of air to be admitted during per each opening period of the air inlet valve 10, is admitted into the cylinder before the top dead center and high velocity inflow is obtained at the final stage of the valve opening period. It will be noted in Fig. 4A that the maximum valve lift before the top dead cénter is higher than the maximum valve lift after the top dead center.
10~8390 If it is possible to admit more than 50~ air, of the total amount of air to be admitted during per each opening period of the air inlet valve 10, into the cylinder bedore the top dead center, the valve lift diagram shown in Fig. 4B is acceptable.
Referring again to Fig. 3, thé relationship between the opening periods X and Y of the exhaust and intake valves 9 and 8 is substantially the same as the con-ventional engines. The opening timing of the intake valve 8 may be delayed slightly, if desired. The scavenging efficiency is increased when the closing timing of the exhaust valve 9 is delayed to increase the valve overlap between the exhaust and air inlet valves 9 and 10. Power output is increased when the closing timing of the air inlet valve 10 is delayed to increase the amount of air within the cylinder 1.
Preferably, the valve overlap between the exhaust valve 8 and air inlet valve 9 is set to be longer under full load conditions than under part load conditions, as shown in Fig. 7 in which the opening perlods of the air inlet valve 9 under full load conditions and under part load conditions are denoted by Zl and Z2' respec-tively. This results in an increase of power output under full load conditions and in low fuel consumption and low emission under part load conditions.
10"8390 , The operation of the engine of this invention will be explained in the following description.
It is recognized that the rate of residual gas of the charge in a cylinder is more than 10% at low engine speed range under full load conditions, causing a low torque at this speed range, while, the rate residual gas at high speed range under full load conditions is not so high and ranges from 3~ to 8%.
According to the invention, such residual gas is expelled from the cylinder 1 and replaced with pure air and the air fuel ratio of the air fuel mixture to be induced into the cylinder 1 is set, under full load conditions of the engine, so that the air fuel ratio of the charge in the cylinder 1 at the end of the intake stroke will become from about 12 to 14. As a result, the energy produced by one combustion process in the cylinder 1 is increased by an amount corresponding to the amount of residual gas expelled by pure air from the cylinder 1, and thus the engine of this invention produce more torque under full load conditions than the con-ventional engine, as shown in Fig. 5 in which the torque by the engine of this invention is shown by solid curve and that by the conventional engine by dashed curve.
The experimental result, as shown in Fig. 5, exhibits that torque has increased by 5% to 15% at low engine speed 10~8390 range under full load conditions and by 5~ at high engine speed range under full load condition. This corresponds to an increase by 5% to 15% in actual cylinder stroke volume, and thus results in an increase of power per unit weight of the engine.
Under part load conditions, the air fuel ratio of air fuel mixture to be inducted into the cylinder 1 is set so that the air fuel ratio within the cylinder 1 at the end of the intake stroke will become not less than the stoichiometry. Stable combustion on such lean air fuel mixture is possible not only because of the replacement of the residual gas with air, but because of a swirl generated by air admitted into the cylinder through the auxiliary intake port bore 7 during the swirl generating phase. The swirl causes an increase o flame propagation speed, thus enabling completion of combustion of such lean air fuel mixture within a limited time.
Because lean air fuel mixture is combusted with the presence of no residual gas under part load conditions, fuel consumption and HC and CO levels are lowered under these conditions. Because excess oxygen is present within the exhaust gas under part load conditions, ad-mission of secondary air to promote oxidation of HC and Co is unnecessary. To reduce NOx level, it is necessary to effect exhaust gas recirculation under part load 10~8390 conditions.
It is recognized that the rate of residual gas of the charge in a cylinder is from about 15% to 30~ under idle and deceleration conditions, causing unstable operation of an engine and frequent misfiring because of the dilution of the combustible-mixture by such residual gas. Thus in the conventional engine it is impossible to operate the engine on the charge including a lean air fuel mixture under these conditions.
However, in the engine of this invention, because such increased residu~l gas is expelled and replaced with pure air and becasue air swirling around the cylinder axis causes an increase of flame propagation speed, stable combustion with lean air fuel mixture is possible under idle and deceleration conditions. As a result, fuel consumption and emission are lowered under these con-ditions.
Preferably, in the engine of this invention, the opening timing of the intake valve 8 is around the top dead center position or delayed under part load, idle and deceleration conditions to reduce the valve overlap between the intake and exhaust valves 8 and 9 so as to minimize mixing of the residual gas with fresh air fuel mixture.
Preferably the closing timing of the air inlet ~0~339~
valve 10 is delayed under part load, idle and decele- -ration conditions than under full load conditions, to such a degree that the opening period of the air inlet valve 9 terminates at the final stage of the intake stroke (see Fig. 7), to elongate a swirl generating phase in which air is admitted, under préssure, into the cylinder 1 through the additional intake port 7 to swirl around the cylinder axis.
Fig. 11 shows another timing diagram for the air inlet valve 10. The opening period which overlaps the exhaust and intake stroke is denoted by A, and the opening period which overlaps the intake and compression stroke is denoted by B. The valve lift diagram for the opening period A and that for the opening period for the opening period B are also shown. Fig. 12 shows a cam profile for the air inlet valve 10 which has the timing diagram and lift diagram shown in Fig. 11.
During the opening period A, a scavenging phase takes place, while, during the opening period B, a swirl generating phase taken place. As will be noted from Fig. 11, the maximum valve lift during the opening period A is higher than the maximum valve lift during the opening period B so as to secure a scavenging air great enough to expel the residual gas during the scavenging 2~ phase and a high-speed jet of air, which swirls the 1~"83~0 charge in the cylinder 1 around the cylinder axis and lasts till the instance of ignition during the swirl generating phase.
The swirl generating phase initiates at the last half portion of the intake stroke and terminates at the front half of the compression stroke. Because the swirl generating phase will not occur during the first or initial portion of the intake stroke, loss of volumetric efficiency of the air fuel mixture drawn into the cylinder 1 from the intake port bore 5 has been minimized. Because the swirl generating phase extends into the first half of the initial portion of the compression stroke, swirl is sustained until the piston 2 approaches the top dead center during the compression stroke. This results in a power up, low fuel consumption and low emission under all operating conditions of the engine.
Referring to Fig. 2B, there is shown an alternative example of a valve arrangement to that shown in Fig. 2A.
The valve arrangement shown in Fig. 2B differs from that shown in Fig. 2A in that, instead of a valve shroud, an additional intake port bore 7 is arranged so as to direct inflowing air to pass along the cylindrical wall of a cylinder 1 so that air admitted into the cylinder through the additional intake port bore 7 will swirl around the cylinder axis.
lQ~83~0 The valve arrangement shown in Fig. 2C differs from that shown in Fig. 2A in that, instead of a valve shroud, an additional intake port bore 7 is configured . to impart a force to inflowing air to swirl around the cylinder axis.
_ 23 -
A solenoid valve 28 is arranged to control flow through the air bleed conduit 26. When not energized, the solenoid valve 28 closes the air bleed conduit 26, while, when energized, it opens the air bleed conduit 26. A
control circuit 30, only diagram~atically shown in Fig. 8, is electrically circuited with the solenoid valve 28.
The control circuit 30 shown in Fig. 8 comprises a clock counter 31 which generates a reset signal 32 at regular intervals. The reset signal 32 is fed to an integrator 33 and also to a flip flop 34 to reset them. An electrical signal 35 representing the engine 10~8390 speed (the engine r.p.m.) is fed to the integrator 33.
An output signal voltage 36 from the integrator 33 rises at a faster rate when the engine speed is high than when the engine speed is low. This output signal voltage 36 is fed to a comparator 37 to which a reference signal voltage 38 representing the engine induction vacuum is fed. The reference signal voltage 38 is higher when the engine induction vacuum is high, i.e., when engine load is low, than when the induction vacuum is low, i.e., when engine load is high. The comparator 37 feeds - a reset signal 39 to the flip flop 34 when the signal 36 exceeds the signal 38. Since time period after the instance of the reset signal 32 to the instance of the reset signal 39 is variable in response to the engine speed and induction vacuum, the flip flop 34 will produce a pulse signal 40 having a pulse width variable in response to the engine speed and induction vacuum. This pulse signal 40 is amplified by means of an amplifier 41 and then used to energize the solenoid valve 28 so that the solenoid will be energized for a time corres-ponding to the pulse width.
Fig. 9A shows a timing diagram representing the condition that the engine speed is high and induction vacuum is low, while Fig. 9B a timing diagram representing the condition that the engine speed is low and induction ~Qg8390 \
vacuum is high. Fig. lO shows a graph plotting the required amount of scavenging air for expelling the residual gas from a cylinder as against the engine speed and induction vacuum. It will now be understood that with the valve 20 the amount of air to be admitted into the cylinder 1 through the additional intake port bore 7 under the control of the air inlet valve 10 (see Fig. 1) will be varied along the graph shown in Fig. 10.
It is found that the best scavenging efficiency has been obtained when more than 50%, by weight, of the total amount, by weight, of air admitted during each opening period of the air inlet valve 10 is admitted into the cylinder l during the scavenging phase before the top dead center position of the piston 2. This can be effected by selecting a cam profile or a valve timing for the air inlet valve 10.
As will be noted from the timing diagram shown in Fig. 3, because the exhaust valve 9 is closing when the air inlet valve 10 begins to open and is almost closed at the top dead center position, the scavenging effici-ency is decreased abruptly as the piston 2 approaches the top dead center.
When the intake valve 8 begins to open, the exhaust gas tends to be drawn into the intake port bore 5 due to vacuum in the intake manifold, and the scavenging - lS -lQ 83~0 efficiency is quite low under this condition.
Thus it will be understood that for the purpose of increasing the scavenging efficiency the cam profile for the air inlet valve 9 should be desinged so that right after the opening of the air inlet valve 9 a great amount of air is admitted into the cylinder 1 to thereby expel as much residual gas from the cylinder as possible before the opening of the intake valve 8.
The opening degree of the air inlet valve 9 should be reduced when the intake valve 8 is opening to increase the inflow velocity of air thereby generating a strong swirl which is effective in increasing the combustion speed.
Therefore, as shown in Fig. 4A the valve lift diagram for the air inlet valve 9 should preferably be set so that a great amount of air is admitted into the cylinder 1 at the initial stage of the valve opening period and more than 50% air, of the total amount of air to be admitted during per each opening period of the air inlet valve 10, is admitted into the cylinder before the top dead center and high velocity inflow is obtained at the final stage of the valve opening period. It will be noted in Fig. 4A that the maximum valve lift before the top dead cénter is higher than the maximum valve lift after the top dead center.
10~8390 If it is possible to admit more than 50~ air, of the total amount of air to be admitted during per each opening period of the air inlet valve 10, into the cylinder bedore the top dead center, the valve lift diagram shown in Fig. 4B is acceptable.
Referring again to Fig. 3, thé relationship between the opening periods X and Y of the exhaust and intake valves 9 and 8 is substantially the same as the con-ventional engines. The opening timing of the intake valve 8 may be delayed slightly, if desired. The scavenging efficiency is increased when the closing timing of the exhaust valve 9 is delayed to increase the valve overlap between the exhaust and air inlet valves 9 and 10. Power output is increased when the closing timing of the air inlet valve 10 is delayed to increase the amount of air within the cylinder 1.
Preferably, the valve overlap between the exhaust valve 8 and air inlet valve 9 is set to be longer under full load conditions than under part load conditions, as shown in Fig. 7 in which the opening perlods of the air inlet valve 9 under full load conditions and under part load conditions are denoted by Zl and Z2' respec-tively. This results in an increase of power output under full load conditions and in low fuel consumption and low emission under part load conditions.
10"8390 , The operation of the engine of this invention will be explained in the following description.
It is recognized that the rate of residual gas of the charge in a cylinder is more than 10% at low engine speed range under full load conditions, causing a low torque at this speed range, while, the rate residual gas at high speed range under full load conditions is not so high and ranges from 3~ to 8%.
According to the invention, such residual gas is expelled from the cylinder 1 and replaced with pure air and the air fuel ratio of the air fuel mixture to be induced into the cylinder 1 is set, under full load conditions of the engine, so that the air fuel ratio of the charge in the cylinder 1 at the end of the intake stroke will become from about 12 to 14. As a result, the energy produced by one combustion process in the cylinder 1 is increased by an amount corresponding to the amount of residual gas expelled by pure air from the cylinder 1, and thus the engine of this invention produce more torque under full load conditions than the con-ventional engine, as shown in Fig. 5 in which the torque by the engine of this invention is shown by solid curve and that by the conventional engine by dashed curve.
The experimental result, as shown in Fig. 5, exhibits that torque has increased by 5% to 15% at low engine speed 10~8390 range under full load conditions and by 5~ at high engine speed range under full load condition. This corresponds to an increase by 5% to 15% in actual cylinder stroke volume, and thus results in an increase of power per unit weight of the engine.
Under part load conditions, the air fuel ratio of air fuel mixture to be inducted into the cylinder 1 is set so that the air fuel ratio within the cylinder 1 at the end of the intake stroke will become not less than the stoichiometry. Stable combustion on such lean air fuel mixture is possible not only because of the replacement of the residual gas with air, but because of a swirl generated by air admitted into the cylinder through the auxiliary intake port bore 7 during the swirl generating phase. The swirl causes an increase o flame propagation speed, thus enabling completion of combustion of such lean air fuel mixture within a limited time.
Because lean air fuel mixture is combusted with the presence of no residual gas under part load conditions, fuel consumption and HC and CO levels are lowered under these conditions. Because excess oxygen is present within the exhaust gas under part load conditions, ad-mission of secondary air to promote oxidation of HC and Co is unnecessary. To reduce NOx level, it is necessary to effect exhaust gas recirculation under part load 10~8390 conditions.
It is recognized that the rate of residual gas of the charge in a cylinder is from about 15% to 30~ under idle and deceleration conditions, causing unstable operation of an engine and frequent misfiring because of the dilution of the combustible-mixture by such residual gas. Thus in the conventional engine it is impossible to operate the engine on the charge including a lean air fuel mixture under these conditions.
However, in the engine of this invention, because such increased residu~l gas is expelled and replaced with pure air and becasue air swirling around the cylinder axis causes an increase of flame propagation speed, stable combustion with lean air fuel mixture is possible under idle and deceleration conditions. As a result, fuel consumption and emission are lowered under these con-ditions.
Preferably, in the engine of this invention, the opening timing of the intake valve 8 is around the top dead center position or delayed under part load, idle and deceleration conditions to reduce the valve overlap between the intake and exhaust valves 8 and 9 so as to minimize mixing of the residual gas with fresh air fuel mixture.
Preferably the closing timing of the air inlet ~0~339~
valve 10 is delayed under part load, idle and decele- -ration conditions than under full load conditions, to such a degree that the opening period of the air inlet valve 9 terminates at the final stage of the intake stroke (see Fig. 7), to elongate a swirl generating phase in which air is admitted, under préssure, into the cylinder 1 through the additional intake port 7 to swirl around the cylinder axis.
Fig. 11 shows another timing diagram for the air inlet valve 10. The opening period which overlaps the exhaust and intake stroke is denoted by A, and the opening period which overlaps the intake and compression stroke is denoted by B. The valve lift diagram for the opening period A and that for the opening period for the opening period B are also shown. Fig. 12 shows a cam profile for the air inlet valve 10 which has the timing diagram and lift diagram shown in Fig. 11.
During the opening period A, a scavenging phase takes place, while, during the opening period B, a swirl generating phase taken place. As will be noted from Fig. 11, the maximum valve lift during the opening period A is higher than the maximum valve lift during the opening period B so as to secure a scavenging air great enough to expel the residual gas during the scavenging 2~ phase and a high-speed jet of air, which swirls the 1~"83~0 charge in the cylinder 1 around the cylinder axis and lasts till the instance of ignition during the swirl generating phase.
The swirl generating phase initiates at the last half portion of the intake stroke and terminates at the front half of the compression stroke. Because the swirl generating phase will not occur during the first or initial portion of the intake stroke, loss of volumetric efficiency of the air fuel mixture drawn into the cylinder 1 from the intake port bore 5 has been minimized. Because the swirl generating phase extends into the first half of the initial portion of the compression stroke, swirl is sustained until the piston 2 approaches the top dead center during the compression stroke. This results in a power up, low fuel consumption and low emission under all operating conditions of the engine.
Referring to Fig. 2B, there is shown an alternative example of a valve arrangement to that shown in Fig. 2A.
The valve arrangement shown in Fig. 2B differs from that shown in Fig. 2A in that, instead of a valve shroud, an additional intake port bore 7 is arranged so as to direct inflowing air to pass along the cylindrical wall of a cylinder 1 so that air admitted into the cylinder through the additional intake port bore 7 will swirl around the cylinder axis.
lQ~83~0 The valve arrangement shown in Fig. 2C differs from that shown in Fig. 2A in that, instead of a valve shroud, an additional intake port bore 7 is configured . to impart a force to inflowing air to swirl around the cylinder axis.
_ 23 -
Claims (40)
1. A method of operating a four-stroke reciprocatory internal combustion engine having a cylinder with a piston reciprocating therein, said method comprising:
a first step of admitting air under pressure into the cylinder during a scavenging phase which overlaps the final portion of the exhaust stroke of the piston so as to scavenge the cylinder:
a second step of inducting air fuel mixture into the cylinder during the intake stroke of the piston; and a third step of admitting air under pressure into the cylinder during a swirl generating phase which overlaps a portion of the intake stroke of the piston which follows said exhaust stroke so that air under pressure mixes with said air fuel mixture and causes the resultant charge to swirl around the cylinder axis.
a first step of admitting air under pressure into the cylinder during a scavenging phase which overlaps the final portion of the exhaust stroke of the piston so as to scavenge the cylinder:
a second step of inducting air fuel mixture into the cylinder during the intake stroke of the piston; and a third step of admitting air under pressure into the cylinder during a swirl generating phase which overlaps a portion of the intake stroke of the piston which follows said exhaust stroke so that air under pressure mixes with said air fuel mixture and causes the resultant charge to swirl around the cylinder axis.
2. A method as claimed in claim 1, in which said swirl generating phase overlaps and succeeds said scavenging phase.
3. A method as claimed in Claim 1, in which the amount, by weight, of air admitted into the cylinder during said scavenging phase is dependent upon operating conditions of the engine.
4. A method as claimed in Claim 2, in which the amount, by weight, of air admitted into the cylinder during said scavenging phase before the top dead center position of the piston is more than 50% of the total amount, by weight, of air admitted into the cylinder during said scavenging phase and the succeeding swirl generating phase.
5. A method as claimed in Claim 2, in which the termination of said swirl generating phase is delayed under part load conditions, idle condition and decel-eration conditions, than under full load conditions of the engine.
6. A method as claimed in Claim 5, in which, under full load conditions of the engine, the air fuel ratio of said air fuel mixture is set so that the air fuel ratio within said cylinder at the end of the intake stroke is from 12 to 14, and in which, under part load conditions of the engine, the air fuel ratio of said air fuel mixture is set so that the air fuel ratio within said cylinder at the end of the intake stroke is not less than the stoichiometry.
7. A method as claimed in Claim 1, in which said swirl generating phase overlaps the compression stroke too.
8. A method as claimed in Claim 2, in which there is provided an air inlet valve which opens to initiate said scavenging phase and closes to terminate said swirl generating phase.
9. A method as claimed in Claim 8, in which the maximum valve lift of said air inlet valve during said scavenging phase before the top dead center position of said piston is higher than during said swirl generating phase after the top dead center position of said piston.
10. A method as claimed in Claim 7, in which there is provided an air inlet valve which opens to initiate said scavenging phase and closes to terminate said swirl generating phase and which opens again to initiate said swirl generating phase and then closes to terminate said swirl generating phase.
11. A method as claimed in Claim 10, in which the maximum valve lift of said air inlet valve during said scavenging phase is higher than the maximum valve lift of said air inlet valve during said swirl generating phase .
12. A method of operating a four-stroke reciprocatory internal combustion engine having a cylinder with a piston reciprocating therein, said method comprising:
a step of admitting air under pressure into the cylinder during a scavenging phase which overlaps the exhaust stroke of the piston so as to scavenge the cylinder;
a step of inducting air fuel mixture into the cylinder during the intake stroke of the piston;
a step of admitting air under pressure into the cylinder during a swirl generating phase which overlaps the intake stroke of the piston so as to swirl said air fuel mixture around the cylinder axis; and a step of controlling said air fuel mixture in response to operating conditions of the engine such that under full load conditions of the engine, the air fuel ratio of said air fuel mixture is set so that the air fuel ratio (A/F) of the charge in the cylinder is from 12 to 14;
under part load conditions of the engine, the air fuel ratio of said air fuel mixture is set so that the air fuel ratio (A/F) of the charge in the cylinder is not less than the stoichiometry; and under idle and deceleration conditions, the air fuel ratio of said air fuel mixture is set so that the air fuel ratio (A/F) of the charge in the cylinder is around the stoichiometry.
a step of admitting air under pressure into the cylinder during a scavenging phase which overlaps the exhaust stroke of the piston so as to scavenge the cylinder;
a step of inducting air fuel mixture into the cylinder during the intake stroke of the piston;
a step of admitting air under pressure into the cylinder during a swirl generating phase which overlaps the intake stroke of the piston so as to swirl said air fuel mixture around the cylinder axis; and a step of controlling said air fuel mixture in response to operating conditions of the engine such that under full load conditions of the engine, the air fuel ratio of said air fuel mixture is set so that the air fuel ratio (A/F) of the charge in the cylinder is from 12 to 14;
under part load conditions of the engine, the air fuel ratio of said air fuel mixture is set so that the air fuel ratio (A/F) of the charge in the cylinder is not less than the stoichiometry; and under idle and deceleration conditions, the air fuel ratio of said air fuel mixture is set so that the air fuel ratio (A/F) of the charge in the cylinder is around the stoichiometry.
13. An internal combustion engine comprising:
. means defining a cylinder having a combustion chamber;
an intake means for inducting air fuel mixture chamber into said combustion chamber during an induction phase of said engine, said intake means including a first inlet valve for con-trolling fluid communication between said intake means and said combustion chamber;
an exhaust means for exhausting the exhaust gas resulting from the combustion of said air fuel mixture from said combustion chamber during an exhaust phase of said engine, said exhaust means including an exhaust valve for controlling fluid communication between said combustion chamber and said exhaust means;
an additional intake means for admitting air under pressure into said cylinder and which is so constructed and arranged as to direct said air under pressure into said cylinder in a direction substantially tangential with respect to the wall of said cylinder so that said air under pressure swirls around said cylinder in one rotational direction, said additional intake means including a pump driven by said engine which supplies said air under pressure, a second inlet valve for controlling the fluid communication between said pump and said combustion chamber, and means operatively connected to said second inlet valve for opening it during a scavenging phase of said exhaust phase so as to scavenge the hot residual gases from-said cylinder and during a swirl generating phase of said induction phase so that said air under pressure mixes with said air fuel mixture fed into said combustion chamber from said intake means and induces the resultant air fuel mixture to swirl in said one rotational direction.
. means defining a cylinder having a combustion chamber;
an intake means for inducting air fuel mixture chamber into said combustion chamber during an induction phase of said engine, said intake means including a first inlet valve for con-trolling fluid communication between said intake means and said combustion chamber;
an exhaust means for exhausting the exhaust gas resulting from the combustion of said air fuel mixture from said combustion chamber during an exhaust phase of said engine, said exhaust means including an exhaust valve for controlling fluid communication between said combustion chamber and said exhaust means;
an additional intake means for admitting air under pressure into said cylinder and which is so constructed and arranged as to direct said air under pressure into said cylinder in a direction substantially tangential with respect to the wall of said cylinder so that said air under pressure swirls around said cylinder in one rotational direction, said additional intake means including a pump driven by said engine which supplies said air under pressure, a second inlet valve for controlling the fluid communication between said pump and said combustion chamber, and means operatively connected to said second inlet valve for opening it during a scavenging phase of said exhaust phase so as to scavenge the hot residual gases from-said cylinder and during a swirl generating phase of said induction phase so that said air under pressure mixes with said air fuel mixture fed into said combustion chamber from said intake means and induces the resultant air fuel mixture to swirl in said one rotational direction.
14. An internal combustion engine as claimed in claim 13, wherein said means defining a cylinder having a combustion chamber includes:
a piston reciprocatively disposed in said cylinder and a cylinder head secured to said cylinder to define said combustion chamber.
a piston reciprocatively disposed in said cylinder and a cylinder head secured to said cylinder to define said combustion chamber.
15. An internal combustion engine as claimed in claim 14, in which said intake means includes an intake port bore which extends through said cylinder to open into said com-bustion chamber and which cooperates with said first inlet valve, said exhaust means includes an exhaust port bore which extends through said cylinder head to open into said combustion chamber and which cooperates with said exhaust valve, and said additional intake means includes an additional intake bore which extends through said cylinder head to open into said combustion chamber and which cooperates with said second inlet valve.
16. An internal combustion engine as claimed in claim 15, in which said first inlet valve is disposed downs-tream of said air inlet valve with respect to the direction of the swirl in said one rotational direction and the exhaust valve is disposed downstream of intake valve with respect to the direction of the swirl in said one rotational direction, whereby the efficiency of scavenging will be increased during said scavenging phase and inflowing air fuel mixture entering said combustion chamber via said intake port bore will not be resisted by the swirling air.
17. An engine as claimed in claim 16, in which a spark plug is mounted to said cylinder head with an electrode thereof exposed to said combustion chamber at a location positioned downstream of said intake valve and upstream of said exhaust valve, with respect to the direction of the swirl in said one rotational direction.
18. An engine as claimed in claim 16, in which said air inlet valve has a valve shroud.
19. An engine as claimed in claim 16, in which said additional intake port bore is arranged so as to direct inflowing air to pass along the cylindrical wall of said cylinder.
20. An engine as claimed in claim 16, in which said additional intake port bore is configured to impart a force to the inflowing air under pressure to swirl around the cylinder axis of said cylinder.
21. An engine as claimed in claim 17, in which said additional intake means comprises a means for controlling the amount of air to be admitted into said cylinder through said additional intake port bore during said scavenging phase and swirl generating phase in response to operating conditions of the engine.
22. An engine as claimed in claim 15, in which said additional intake means further comprises: a surge tank fluidly disposed intermediate said air pump and said additional intake port bore; a passage means whereby air passes from said surge tank to said additional intake port bore; a flow control valve fluidly disposed in said passage means to control flow therethrough; a vacuum servo means for actuating said flow control valve; a source of constant vacuum; a vacuum passage connecting said source of constant vacuum to said vacuum servo means; an air bleed passage having one end connected to said vacuum passage and an opposite end opening to the atmosphere;
a solenoid valve for controlling flow through said air bleed passage; and control circuit means for energizing said solenoid valve in response to operating conditions of the engine.
a solenoid valve for controlling flow through said air bleed passage; and control circuit means for energizing said solenoid valve in response to operating conditions of the engine.
23. An engine as claimed in claim 15, in which said swirl generating phase overlaps and succeeds said scavenging phase.
24. An engine as claimed in claim 23, in which said air inlet valve opens to initiate said scavenging phase and closes to terminate said air injection phase, and in which the maximum valve lift of said air inlet valve during said scavenging phase before the top dead center position of said piston is higher than the maximum valve lift of said air inlet valve during said swirl generating phase after the top dead center position of said piston, whereby a great amount of air is admitted into said cylinder during said scavenging phase and inflow velocity of air as admitted into said cylinder is increased during said swirl generating phase.
25. An engine as claimed in claim 24, in which the amount of air to be admitted into said cylinder during said scavenging phase before the top dead center position of said piston is more than approximately 50% of total amount of air to be admitted into said cylinder during said scavenging phase and during said swirl generating phase.
26. An engine as claimed in claim 24, in which the closing timing of said air inlet valve is delayed under part load conditions of the engine rather than under full load con-ditions of the engine.
27. An engine as claimed in claim 15, in which said swirl generating phase overlaps the compression stroke of said piston, too.
28. An engine as claimed in claim 27, in which said air inlet valve opens to initiate said scavenging phase and closes to terminate said scavenging phase and said air inlet valve opens again to initiate said swirl generating phase and then closes to terminate said swirl generating phase, and in which the maximum valve lift of said air inlet valve during said scavenging phase is higher than the maximum valve lift of said air inlet valve during said swirl generating phase, whereby a great amount of air is admitted into said cylinder during said scavenging phase and inflow velocity of air as admitted into said cylinder is increased during said swirl generating phase.
29. An engine as claimed in claim 21, in which, under full load conditions of the engine, the air fuel ratio of said air fuel mixture is set so that the air fuel ratio within said cylinder is approximately from 12 to 14 at the end of the intake stroke of said piston, and in which, under part load conditions of the engine, the air fuel ratio of said air fuel mixture is set so that the air fuel ratio within said cylinder is not less than the stoichiometry.
30. An engine as claimed in claim 13, in which said pump takes the form of an air compressor operatively connected to a turbine fluidly disposed in the exhaust gas issued from said engine.
31. In a method of operating an internal combustion entine, the steps of, compressing air via a pump driven by said engine;
storing the compressed air from said pump in a surge tank fluidly interposed between said pump and said engine;
exhausting the combustion gases from the combustion chamber of said engine via an exhaust valve;
scavenging the residual combustion gases from the combustion chamber by introducing compressed air into said com-bustion chamber by opening a first inlet valve which controls the fluid communication between said surge tank and said com-bustion chamber, during the final stage of the exhaust phase of said engine;
inducting an air fuel mixture into said combustion chamber by opening a second inlet valve during an induction phase of said engine;
swirling the air fuel charge in said combustion cham-ber by introducing compressed air from said surge tank into said combustion chamber by opening said first inlet valve during a portion of the induction phase of said engine so that said compressed air mixes with said air fuel mixture and induces the resultant air fuel charge to swirl in said combustion chamber;
controlling the volume of compressed air permitted to flow from said surge tank to said combustion chamber by operating control valve means fluidly interposed between said surge tank and said combustion chamber; and operating said control valve means in response to signals produced by sensing engine speed and engine load.
storing the compressed air from said pump in a surge tank fluidly interposed between said pump and said engine;
exhausting the combustion gases from the combustion chamber of said engine via an exhaust valve;
scavenging the residual combustion gases from the combustion chamber by introducing compressed air into said com-bustion chamber by opening a first inlet valve which controls the fluid communication between said surge tank and said com-bustion chamber, during the final stage of the exhaust phase of said engine;
inducting an air fuel mixture into said combustion chamber by opening a second inlet valve during an induction phase of said engine;
swirling the air fuel charge in said combustion cham-ber by introducing compressed air from said surge tank into said combustion chamber by opening said first inlet valve during a portion of the induction phase of said engine so that said compressed air mixes with said air fuel mixture and induces the resultant air fuel charge to swirl in said combustion chamber;
controlling the volume of compressed air permitted to flow from said surge tank to said combustion chamber by operating control valve means fluidly interposed between said surge tank and said combustion chamber; and operating said control valve means in response to signals produced by sensing engine speed and engine load.
32. A method of operating an internal combustion engine as claimed in claim 31, further comprising the step of:
instigating said step of swirling at the beginning of said induction phase so that compressed air is continuously introduced to said combustion chamber from said final stage of said exhaust phase to the end of said portion of said induction phase.
instigating said step of swirling at the beginning of said induction phase so that compressed air is continuously introduced to said combustion chamber from said final stage of said exhaust phase to the end of said portion of said induction phase.
33. A method of operating an internal combustion engine as claimed in claim 31, further comprising the steps of:
instigating said step of swirling during the final stage of said induction phase; and continuing said step of swirling into the initial stage of the compression phase of said engine.
instigating said step of swirling during the final stage of said induction phase; and continuing said step of swirling into the initial stage of the compression phase of said engine.
34. A method of operating an internal combustion engine as claimed in claim 31, further comprising the step of:
controlling the amount of air introduced into said combustion chamber through said first inlet valve during said scavenging step according to a schedule which increases with engine speed decrease and increase in induction vacuum res-pectively.
controlling the amount of air introduced into said combustion chamber through said first inlet valve during said scavenging step according to a schedule which increases with engine speed decrease and increase in induction vacuum res-pectively.
35. An internal combustion engine as claimed in claim 13, wherein said combustion chamber takes the form of a single discrete variable volume space, a surge tank is disposed between said pump and said engine for storing the air compressed by said pump and which further includes control valve means disposed between said surge tank and said second inlet valve for controlling the volume of com-pressed air which is permitted to flow from said surge tank toward said combustion chamber, said control valve means being responsive to signals indicative of engine speed and engine load.
36. An internal combustion engine as claimed in claim 35, wherein said second inlet valve is opened during the final portion of the exhaust phase of said engine and closed during the initial portion of said induction phase so that air is continuously introduced into said combustion chamber and said scavenging is immediately followed by said swirling.
37. An internal combustion engine as claimed in claim 35, wherein said second inlet valve is opened during the final portion of said exhaust phase, closed for the initial of the subsequent induction phase, opened during the final portion of said induction phase and maintained open into the initial portion of the subsequent compression phase.
38. An internal combustion engine as claimed in claim 35, wherein said control valve means controls the amount of air permitted to flow to the combustion chamber in accordance with a schedule which increases with increase in engine induction vacuum and decrease in engine speed respectively.
39. An internal combustion engine as claimed in claim 35, further comprising:
an inlet valve cam which has a high lift portion and a low lift portion, said high lift portion being arranged to lift said second inlet valve during said exhaust phase so that a relatively large amount compressed air is introduced into said combustion chamber to scavenge said residual combustion gases and said low lift portion lifts said second inlet valve during said induction phase so that said compressed air is introduced into said combustion chamber with a high velocity for inducing said swirl.
an inlet valve cam which has a high lift portion and a low lift portion, said high lift portion being arranged to lift said second inlet valve during said exhaust phase so that a relatively large amount compressed air is introduced into said combustion chamber to scavenge said residual combustion gases and said low lift portion lifts said second inlet valve during said induction phase so that said compressed air is introduced into said combustion chamber with a high velocity for inducing said swirl.
40. A method of operating an internal combustion engine as set forth in claim 31 further comprising the steps of:
inducing a high lift of said inlet valve during said step of scavenging so that an adequate volume of compressed air is introduced into said combustion chamber; and inducing a low lift of said inlet valve during said step of swirling so that a stream of high velocity compressed air is introduced into said combustion chamber.
inducing a high lift of said inlet valve during said step of scavenging so that an adequate volume of compressed air is introduced into said combustion chamber; and inducing a low lift of said inlet valve during said step of swirling so that a stream of high velocity compressed air is introduced into said combustion chamber.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP51-133856 | 1976-11-08 | ||
| JP51133856A JPS595768B2 (en) | 1976-11-08 | 1976-11-08 | Forced scavenging internal combustion engine |
| JP51-151381 | 1976-12-15 | ||
| JP15138176A JPS5374619A (en) | 1976-12-15 | 1976-12-15 | Forced scavencing internal combustion engine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1098390A true CA1098390A (en) | 1981-03-31 |
Family
ID=26468105
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA290,288A Expired CA1098390A (en) | 1976-11-08 | 1977-11-07 | Four-stroke reciprocatory internal combustion engine and method of operating such an engine |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US4217866A (en) |
| AU (1) | AU504113B1 (en) |
| CA (1) | CA1098390A (en) |
| DE (1) | DE2749730A1 (en) |
Families Citing this family (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU525683B2 (en) * | 1976-12-21 | 1982-11-25 | Malz Nominees Pty. Ltd. | Internal combustion engine |
| JPS6035535B2 (en) * | 1981-04-07 | 1985-08-15 | トヨタ自動車株式会社 | Flow path control device for helical intake port |
| US4526139A (en) * | 1983-09-09 | 1985-07-02 | Medlinsky Edward I | Internal combustion engine |
| YU78487A (en) * | 1986-05-05 | 1990-12-31 | Ingersoll Rand Co | Process and valve assembly for improving mixing of air and fuel |
| US4809649A (en) * | 1987-11-23 | 1989-03-07 | Thomassen International B.V. | Four-stroke internal-combustion engine and procedure for operating such an engine |
| JPH03501400A (en) * | 1988-05-06 | 1991-03-28 | スオミネン、ラウリ | METHODS AND APPARATUS FOR IMPROVING ENGINE OPERATION |
| US5448971A (en) * | 1990-06-20 | 1995-09-12 | Group Lotus Limited | Internal combustion engine and an improved rotary inlet valve for use therewith |
| US5381760A (en) * | 1993-07-09 | 1995-01-17 | Thermal Dynamics, Inc. | Air injection system for internal combustion engines during combustion cycle of operation |
| WO1998042174A2 (en) * | 1997-03-21 | 1998-10-01 | Jaime Ruvalcaba | Improved internal combustion engine |
| FR2841294B1 (en) * | 2002-06-21 | 2007-04-06 | Inst Francais Du Petrole | METHOD FOR CONTROLLING AN INDIRECT INDIRECT INJECTION ENGINE AND ENGINE USING SUCH A METHOD |
| FR2863006B1 (en) | 2003-12-02 | 2006-02-24 | Inst Francais Du Petrole | METHOD FOR CONTROLLING AN OVERLAYING MOTOR, IN PARTICULAR AN INDIRECT INJECTION ENGINE, AND ENGINE USING SUCH A METHOD |
| FR2864153B1 (en) | 2003-12-18 | 2006-02-17 | Inst Francais Du Petrole | METHOD FOR CONTROLLING AN INTERNAL COMBUSTION ENGINE SUPERCURRENT TO AT LEAST TWO CYLINDERS AND ENGINE USING SUCH A METHOD |
| DK175664B1 (en) | 2003-12-23 | 2005-01-10 | Ln Systems Aps | Internal combustion engine comprises at least one cylinder with corresponding top piece, piston moving backward and forward in cylinder |
| FR2886342B1 (en) * | 2005-05-24 | 2010-08-27 | Inst Francais Du Petrole | METHOD FOR CONTROLLING SCAN OF BURNED GASES OF AN INDIRECT INJECTION ENGINE, ESPECIALLY SUPERCURRENT MOTOR, AND ENGINE USING SUCH A METHOD |
| FR2901846A1 (en) * | 2006-06-01 | 2007-12-07 | Peugeot Citroen Automobiles Sa | Internal combustion engine for vehicle, has air admission valve connected to cylinders of engine, and make-up air supply unit mounted in parallel with air admission valve on one of cylinders for injecting make-up air in cylinder |
| FR2902463B1 (en) | 2006-06-19 | 2008-08-22 | Inst Francais Du Petrole | INTERNAL COMBUSTION ENGINE WITH INDIRECT INJECTION, ESPECIALLY CONTROLLED IGNITION ENGINE, WITH TWO MEANS OF ADMISSION FOR CARRYING OUT A BRAZING GAS SCAN PHASE |
| FR2904049B1 (en) * | 2006-07-24 | 2012-08-31 | Valeo Sys Controle Moteur Sas | THERMAL MOTOR HAVING TWO ADMISSION DUCTS, ONE OF WHICH IS USED FOR SWEEPING THE COMBUSTION CHAMBER, MODULE FOR MANAGING SUCH A THERMAL MOTOR, AND METHOD FOR MANAGING A THERMAL MOTOR |
| FR2942503B1 (en) | 2009-02-23 | 2011-03-04 | Peugeot Citroen Automobiles Sa | METHOD AND ESTIMATOR OF FRESH AIR MASS IN A COMBUSTION CHAMBER, TOTAL FILLING ESTIMATING METHOD, RECORDING MEDIUM FOR THESE METHODS AND VEHICLE EQUIPPED WITH SAID ESTIMATOR |
| FR2946690B1 (en) * | 2009-06-12 | 2011-06-24 | Inst Francais Du Petrole | METHOD FOR CONTROLLING THE ADMISSION OF A SUPERIOR INTERNAL COMBUSTION ENGINE COMPRISING A BRAZING GAS SCAN OPERATION. |
| FR2959775B1 (en) | 2010-05-07 | 2012-05-25 | Peugeot Citroen Automobiles Sa | METHOD FOR ESTIMATING FRESH AIR QUANTITY, RECORDING MEDIUM AND ESTIMATOR FOR THIS METHOD, VEHICLE EQUIPPED WITH SAID ESTIMATOR |
| US8689878B2 (en) | 2012-01-03 | 2014-04-08 | Baker Hughes Incorporated | Junk basket with self clean assembly and methods of using same |
| CN102562274A (en) * | 2012-02-15 | 2012-07-11 | 麦镇荣 | High-efficiency environment-protecting supercharged engine |
| DE102012204885B3 (en) * | 2012-03-27 | 2013-03-14 | Ford Global Technologies, Llc | Method for operating combustion engine i.e. petrol engine, of vehicle, involves storing map using two operational parameters of combustion engine as input variables in engine control unit in which lambda probe controls air ratio |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE353093C (en) | 1922-05-13 | Emile Henri Auger | Process for cooling internal combustion engines | |
| US1048922A (en) * | 1908-08-03 | 1912-12-31 | Chicago Pneumatic Tool Co | Internal-combustion engine. |
| US1138077A (en) * | 1912-10-22 | 1915-05-04 | Busch Sulzer Bros Diesel Engine Co | Marine-engine installation. |
| US1576357A (en) * | 1917-07-05 | 1926-03-09 | Pierce Josiah | Internal-combustion engine |
| US1297248A (en) * | 1917-09-04 | 1919-03-11 | Harry Ralph Ricardo | Internal-combustion engine. |
| US1512710A (en) * | 1919-09-29 | 1924-10-21 | Potter Edson | Explosion engine |
| US1431547A (en) * | 1920-07-13 | 1922-10-10 | Balwin Harle | Internal-combustion engine |
| DE586119C (en) | 1929-09-12 | 1933-10-16 | Ludwig Laubender | Four-stroke diesel engine with a common inlet and outlet valve, in particular with airless fuel injection |
| DE674142C (en) | 1932-01-03 | 1939-04-05 | Anton Heinrich Alt | Two-stroke internal combustion engine with direct current flushing |
| US2477173A (en) * | 1940-08-10 | 1949-07-26 | Farkas Pierre | Two-stroke internal-combustion engine |
| US2818931A (en) * | 1956-03-19 | 1958-01-07 | Mallory Marion | Internal combustion engine |
| US3046960A (en) * | 1960-09-26 | 1962-07-31 | Fiat Motor Company | Internal combustion engines |
| US3046961A (en) * | 1960-09-26 | 1962-07-31 | Fiat Motor Company | Internal combustion engines |
| US3182645A (en) * | 1963-07-24 | 1965-05-11 | Ora E Wilson | Internal combustion engine |
| US3363612A (en) * | 1965-09-03 | 1968-01-16 | Arthur M. Brenneke | Self-supercharged engine with constant pressure accumulator |
| US3443552A (en) * | 1966-12-13 | 1969-05-13 | Ernest A Von Seggern | Internal combustion engine,fuel supply system and process |
| DE1962114A1 (en) * | 1969-12-11 | 1971-06-16 | Volkswagenwerk Ag | Internal combustion engine with an additional air inlet valve |
| US3630021A (en) | 1970-06-02 | 1971-12-28 | Irving N Bishop | Internal combustion engine including means for reducing emissions |
| JPS5036905U (en) * | 1973-08-09 | 1975-04-17 | ||
| JPS548241Y2 (en) * | 1973-08-09 | 1979-04-17 |
-
1977
- 1977-11-07 DE DE19772749730 patent/DE2749730A1/en not_active Withdrawn
- 1977-11-07 CA CA290,288A patent/CA1098390A/en not_active Expired
- 1977-11-07 US US05/849,509 patent/US4217866A/en not_active Expired - Lifetime
- 1977-11-08 AU AU30470/77A patent/AU504113B1/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| DE2749730A1 (en) | 1978-05-18 |
| US4217866A (en) | 1980-08-19 |
| AU504113B1 (en) | 1979-10-04 |
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